lean duplex
lean duplex
(OP)
Has anyone in this forum used or specofied a lean duplex, such as 2101, 2003, or 2304? If so, what has been your experience? If you have considered using one of these, but decided against it, what were your reasons?
Michael McGuire
http://stainlesssteelforengineers.blogspot.com/





RE: lean duplex
ed
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Corrosion, every where, all the time.
Manage it or it will manage you.
http://www.trent-tube.com/contact/Tech_Assist.cfm
RE: lean duplex
Michael McGuire
http://stainlesssteelforengineers.blogspot.com/
RE: lean duplex
These alloys are seeing use in some plate applications (tanks) that I know of. Usually replacing 304 or 316 and saving money by reducing the weight.
There are very few applications in more highly engineered products. In my case, tubing. The biggest reason is that most companies no longer know the details behind their material selection decisions. They layed all of those guys off years ago.
In order for these alloys to have an advantage you either need to have your product stronger, or you need to be able to make it lighter.
I am having trouble finding companies that have the skills required to re-evaluate designs and take advantage of these features.
I am selling into one place right now. He is not saving any money because he is using the same size tube, but he has gained CSCC resistance over the old 316 part.
= = = = = = = = = = = = = = = = = = = =
Corrosion, every where, all the time.
Manage it or it will manage you.
http://www.trent-tube.com/contact/Tech_Assist.cfm
RE: lean duplex
Any temperature range advantages?
RE: lean duplex
Why not do some model redesigns on items like heat exchangers, or some other common equipment your customers buy 316L for, and show the savings possible? Some customers need spoon feeding.
Michael McGuire
http://stainlesssteelforengineers.blogspot.com/
RE: lean duplex
I have layed out the trade offs for some of them. They just can't make the decision.
As far as temp, just like any duplex or ferritic. You should be above -40F and below 650F. The lean grades are more forgiving than a higher alloy duplex or ferritic. Most of these grades will actually tolerate hours at 1400F before you see much decrease in toughness, as opposed to minutes in higher alloy grades.
= = = = = = = = = = = = = = = = = = = =
Corrosion, every where, all the time.
Manage it or it will manage you.
http://www.trent-tube.com/contact/Tech_Assist.cfm
RE: lean duplex
Will keep that in mind for my next high temp application.
RE: lean duplex
Doesn't anybody make a business of designing and producing heat exchangers, again for instance? They would have a tremendous product advantage if they were to adopt these better alloys.
If it's all done by an in-house maintenance/engineering group, then I see what you're up against.
Michael McGuire
http://stainlesssteelforengineers.blogspot.com/
RE: lean duplex
Purchase of new heat exchanger equipment can be done by several different approaches. As a user of equipment, we can hire an AE firm that would develop a Technical Specification that goes out for bid to companies like TEI, or YUBA (I am only using these two heat exchanger companies as examples, this is not a plug for either of them) that design, fabricate and install these components. The user has handed off all aspects of the job to these companies. The selection of material can come from two sources - the customer, or by the heat exchanger company (TEI or YUBA). If it is by the customer, they can deal direct with the mill supplying the tubing OR go thru the heat exchanger company itself.
The other option for users of heat exchangers is a re-tube of an existing heat exchanger. Again, the user has two options -hire an AE firm to develop a Tech Spec and once again go to YUBA or TEI for their recommendation OR you work with a mechanical contractor and mill that supplies tubing.
This is my opinion – “ user's today seem more adverse to risk and, as such, seem to rely on outside firms to Engineer, Procure and Construct. I personally do not agree with this method of business. I presently work for a company that decided to at least keep some technical core competency to work directly with suppliers like Trent or others to afford the best material selection”.
RE: lean duplex
RE: lean duplex
Experience has also shown that even if there is discolouration on the AL2003 steel the corrosion resistance (from G48 tests) is still far better than that of 316L. Can't give specifics unfortunately in a public forum however.
We went down this route as a lower cost option for deep water pipes (>1000m water depth) instead of temper rolled grades as those can have limited forming ability.
Regards Riadsala
RE: lean duplex
I don’t think it is necessarily fair to say companies don’t have the skills necessary to re-evaluate designs. This may be true in some cases but not in all, or maybe even the majority. Often companies (OEMs or consulting engineers) receive conflicting information from steel suppliers/manufacturers. I’ll give an example. One steel manufacturer’s sales staff was strongly pushing a new lean duplex (2003 and 2101 level, not 2304) to an OEM for an application saying in their literature that the material was suitable for service; I have a copy of the presentation. When speaking with the steel manufacture’s technical people their comment was “Not the application I’d start with”. I heard this comment after I specifically asked the question. Same company with contrasting points of view. If the steel manufacturer cannot present a uniform presentation why should the OEM take the risk?
The use of 2304 in kraft pulping (cooking plant) has been used for several years and it isn’t a stretch to understand that it would work given the alloy content. However, it wasn’t until the last 18-24 months that 2304 was an economic replacement for 2205 in pressurized vessels in kraft cooking liquor applications (digester, white liquor reactor, etc).
I have yet to see the new 2101 or 2003 make in road in pulp and paper in any significant way. In applications comparable for 304L, such as atmospheric storage tanks where API 650 or customer min wall values (normally 5-6 mm) are used it isn’t a cost effective substitute. These tanks, which are normally only insulated in the first 2m for personnel protection can be coated with a variety of coatings (under insulation) which provide SCC resistance and are still less expensive that 2101 or 2003. There is no percentage for anyone to make a change. Even in large (6000 m^3 to 10000 m^3) pulp storage tanks, these are usually carbon steel loose lined with 300 series stainless except the top portion and roof which is 300 series stainless. I have not seen duplex used extensively in these applications except for a project in China.
I’m not trying to cast stones, but these are the experiences I have dealt with.
RE: lean duplex
LDX 2101 round bar has also been used for a wetted application in another pulp mill where 316L shafting in a conveyor suffered what they felt was a mechanical/fatigue failure. LDX 2101 significantly raises the mechanical properties vs 316L (94/65 ksi vs 75/30 ksi minimum UTS/yield).
The lean duplexes (2101 and 2003) are relatively new and have only been commercially offered in flat products for about 1-2 years. Adoption of any new alloy normally takes several years to happen.
RE: lean duplex
Thanks.
RE: lean duplex
Michael McGuire
http://stainlesssteelforengineers.blogspot.com/
RE: lean duplex
Regards,
Brett
RE: lean duplex
Michael McGuire
http://stainlesssteelforengineers.blogspot.com/
RE: lean duplex
I believe that this material will find its way into inventories, eventually.
The real problem could be availability of fittings.
You are right McG, I am not interested in making small diameter welded-to-size tubing. I would galdly make the tube and pipe sizes that are smaller than what Outokumpu wants to deal with. We don't make anything larger than a 4.0" OD.
= = = = = = = = = = = = = = = = = = = =
Rust never sleeps
Neither should your protection
http://www.trent-tube.com/contact/Tech_Assist.cfm
RE: lean duplex
Metengr, as I have read your comments throughout the years in this forum, I have thought many times 'oh to have had a metengr working at xyz plant or company instead of those guys sitting across the table giving me "owl eyes".
My compliments. The TEI and/or Yuba technical people sure better appreciate you.
rmw
PS: this is a metallurgical thread, but dittos for heat transfer.
RE: lean duplex
RE: lean duplex
Michael McGuire
http://stainlesssteelforengineers.blogspot.com/
RE: lean duplex
RE: lean duplex
Michael McGuire
http://stainlesssteelforengineers.blogspot.com/
RE: lean duplex
= = = = = = = = = = = = = = = = = = = =
Rust never sleeps
Neither should your protection
http://www.trent-tube.com/contact/Tech_Assist.cfm
RE: lean duplex
Michael McGuire
http://stainlesssteelforengineers.blogspot.com/
RE: lean duplex
Two major orders. One for a hot process water piping system in a synthetic rubber plant. It replaced 304L that was suffering underinsulation cracking in less than 9 months time. Roughly 500 feet is installed
Another is for reactor internals for a process to make biodegradable plastics. Used as a cost down to 316L. 40,000 feet involved. System to be installed in mid 2007.
RE: lean duplex
RE: lean duplex
http://www.oceanint.com/content3/
RE: lean duplex
RE: lean duplex
And by the way, don't use the letters in front of 2205. The recognised common name in ASTM for the grade is '2205'.
= = = = = = = = = = = = = = = = = = = =
Rust never sleeps
Neither should your protection
http://www.trent-tube.com/contact/Tech_Assist.cfm
RE: lean duplex
RE: lean duplex
Michael McGuire
http://stainlesssteelforengineers.blogspot.com/
RE: lean duplex
(Trent Tube only works up through 4" outside diameter (3 1/2" pipe))
= = = = = = = = = = = = = = = = = = = =
Rust never sleeps
Neither should your protection
http://www.trent-tube.com/contact/Tech_Assist.cfm
RE: lean duplex